package lanqiao;

import java.util.Scanner;

public class ParkingFee {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入停车时长");
        int n = sc.nextInt();
        int cost = 0;
        if(n > 15) {
            cost = (n / 15) * 2;
        }else {
            cost = 0;
        }
        System.out.println(cost);
    }
}
